Electrical failure of transformer coils, transposed cables, and other electrical equipment can occur when short circuit forces or mechanical abuse damage insulation. The mechanical strength of insulated coils and cables can be increased by bonding the individual insulated electrical conductors together into a single mass. This has been accomplished by placing adhesive coated paper in between the layers of conductors. However, while this increases strength and reduces insulation damage, it also increases the cellulosic content of the electrical apparatus. Cellulose is undesirable if certain dielectric fluids are present because they react with cellulose to produce compounds which increase the conductivity of the fluid. Another technique for forming a single mass out of multiple conductors is to cover the conductors with an adhesive either before or after the conductors have been juxtaposed. While this technique has also worked, it involves an additional step, and difficulties may be encountered in obtaining good adhesion between the insulation and the adhesive.